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 Elements for valid contract • Agreement  • Object • Cause • Form • Legal capacity  • Perfect consent   Types of contract  • Lump sum –fixed price  • Re-measurement / unit price • Reimbursable /cost plus   Contracting methods  • Traditional method (design –bid-build) • Design& build, Turn key  • Fast Track Choosing suitable form of the FIDIC Priority of documents according to FIDIC 1.      Contract agreement 2.      The letter of acceptance 3.      The letter of tender 4.      General Conditions (FIDIC) 5.      Special conditions 6.      The specifications 7.      The drawings 8.      The schedules 9.      The contractor proposal 10. JV undertaking 11. If any stated in contract agreement or acceptance letter Fidic2017 ...

***  عند وجود الخرسانه في بيئه ضاره سواء كانت من المياه أو التربه تتعرض الخرسانه لمهاجمه من الأملاح والاحماض وهذا يضر بالخرسانه. استخدام اسمنت المقاوم للكبريتات والعزل الجيد الخرسانه يكون حل فعال الي حد كبير لحمايه الخرسانه . الجدول المرفق يوضح انواع الأحماض والاملاح التي تؤثر على الخرسانه وطرق الوقايه من تأثيرها الضار . انواع ‏الخوازيق ‏الخرسانيه ‏وطرق ‏تنفيذها  

تستخدم الخوازيق الخرسانية في الأعمال الإنشائية.  1- خوازيق بنوتو BENOTO يتم الحفر باستخدام ماسورة مؤقتة او دائمة لسند جوانب الحفر ثم انزال الحديد والصب يستخدم في التربة المسامية الحاملة للمياه في حالة التربة المتماسكة يمكن استخدام النتونيت في سند جوانب الحفر خوازيق شريطية DIAPHRAM WALL 1- تجهيز وصب حائط الدليل 2- تجهيز معلق البنتونيت 3- الحفر 4- وضع البنتونيت 5- انزال الحديد 6- صب الخرسانة 2- الخوازيق الساندة 1- خوازيق متجاورة  adjacent piles    2- خوازيق متلاصقة  contiguous piles  3- خوازيق متقاطعة Secant piles   *يمكن ان تكون الخوازيق المتقاطعة كلها من الخرسانة المسلحة مع مراعاة الغطاء الخرساني اذا تطلب التصميم ذلك 4- خوازيق ستراوس يتم التنقيذ بالحفر اليدوي او الميكانيكي كالاتي 1- تغويص الماسورة بالقطر المطلوب حتي تصل ال العمق المطلوب 2- صب الخرسانة حتي منسوب اسفل الحديد 3- انزال الحديد 4- استكمال الصب 5- سحب الماسورة *تصمم كخوازيق ارتكاز فقط *تستخدم لاقطار حتي 50سم واطوال 20مترميكانيكيا  *لايقل عدد تجارب الت...

In concrete structures there are many different methods that can structure engineer uses in demolition process   1-Top Down — Manual Method Top down method discussed below is the method that proceeds from the roof to ground in a general trend, there are particular sequences of demolition which may vary, depending on site conditions and structural elements to be demolished. For reinforced concrete buildings, jack hammers are commonly used to break down the concrete. Oxy-acetylene torch could be used to cut the reinforcements. The structural elements shall be broken down gradually or by alternate methods as described in the following sub-section. The reinforcements shall remain until all the concrete connecting to or supported by the reinforcement is broken away or when its support is no longer required. Demolition Sequence (A) All cantilevered structures, canopies, verandahs and features attached to the external walls shall first be demolished prior to demolition of main buildi...

Prior to carrying out any building demolition, detailed building appraisal by means of surveys and appropriate assessments shall be required. In general, the surveys shall include a Building Survey and a Structural Survey with photographs or videos taken for future reference. Based on the findings of these surveys, a demolition plan shall then be prepared Building Survey Prior to the Building Survey, the existing record plan, including layout plan showing adjoining properties, pedestrian walkway, roads and street, etc. shall be retrieved. Potential dangerous areas, e.g., abnormal layouts, presence of enclosed voids, and non-ventilated light wells which may trap obnoxious gas at the bottom. Unless the Building Survey reviews that no obvious hazardous material is present in the building, the Authorized Person shall cause proper sampling and testing for the hazardous materials; Prior to the Structural Survey, the existing record layout, structural framing plans and structural details shal...

               This series of paragraphs outlines good practices for the planning and implementation of demolition works for different types of buildings. All demolishing works shall be done under supervision of authorized Person. Safety of pedestrians, public properties, traffic and workers must be maintained. This manual include 10 ways for demolition, experienced structural engineer should decide which manner is suitable refer to site conditions and environmental considerations. Methods of demolition

All of this types used in Concrete structures to certain purpose . Epoxy grout consist of epoxy resin, epoxy harder and aggregate. It's commonly used for repairing hairline cracks and cavities in concrete structures. Cement grout is formed by mixing cement powder with water. It's commonly used to filling gaps and voids in structures. Cement mortar is basically mixture of cement, water and sand. It's used as bedding for concrete Krebs and tiles. 5 types of Portland Cement

 In structure design of concrete structures  Open stirrups is used to resist shear force only. Closed stirrups is used to resist both shear force and torsion. Steel Rebar color chart

1. stainless steel it's the best material for corrosion resistance among other materials. 2. Epoxy coatings: use epoxy coatings above steel can prevent corrosion  3. Galvanized steel : it's used for corrosion resistance but it's lest durability in compromise with epoxy coatings and stainless steel Difference between steel and stainless steel